const fs = require('fs');
const path = require('path');
const readFile = path.join(__dirname, 'gongzi.bak.txt');
const writeFile = path.join(__dirname, 'gongzi.bak.bak.txt');
const readStream = fs.createReadStream(readFile);
const writeStream = fs.createWriteStream(writeFile);
readStream.pipe(writeStream);